Progresso Umano e Sviluppo Sostenibile€¦ · Progresso Umano e Sviluppo Sostenibile Dott.ssa...
Transcript of Progresso Umano e Sviluppo Sostenibile€¦ · Progresso Umano e Sviluppo Sostenibile Dott.ssa...
Progresso Umano e Sviluppo Sostenibile
Dott.ssa Carlotta Raviola
PhotoGreen Lab –Department of Chemistry
University of Pavia Viale Taramelli 12 27100 Pavia-ITALY
email:[email protected]
Web: http://www-2.unipv.it/photogreenlab/
Collegio universitario S. Caterina da Siena
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Chemical industry
and related
Introduction
Transportation
Clothing
Sport
Safety
Food
MedicalOffice
Home
Farming
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Introduction
Asbestos
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IntroductionSeveso
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Introduction
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Introduction
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Sustainable Development
"Sustainable development is
development that meets the needs of
the present without compromising theability of future generations to meet
their own needs".
Gro Harlem Brundtland
(Brundtland Report, 1987)
"Green chemistry is the design ofchemical products and processes that
reduce or eliminate the use or
generation of hazardous substances".
(US EPA, Early 1990s)
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Sezione II, capitolo 19. A substantial use of chemicals is essential to meet
the social and economic goals of the world community and today's best
practice demonstrates that they can be used widely in a cost-effective
manner and with a high degree of safety.
Sustainable Development
1992
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The 12 Principles of Green Chemistry
Paul Anastas
John Warner
Green Chemistry: Theory and Practice, 1998
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The 12 Principles of Green Chemistry
1) It is better to prevent waste than to treat or clean up waste after it has
been created.
2) Synthetic methods should be designed to maximize incorporation of all
materials used in the process into the final product. (Atom Economy)
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The 12 Principles of Green Chemistry
2)
Yield (P1)(%) = actual quantity of products achived (P1)
theoretical quantity of products achievable (P1)*100
Es. actual quantity of products achived (P1)= 60g
theoretical quantity of products achievable(P1) = 80g Yield =60g
80g*100 =75%
Selectivity (P1)(%) = yield of desidered product (%P1)yields of all products (%P1+%P2)
*100
Es. yield of desidered product (%P1)= 75%
amount of substrate converted (%P1+ %P2)= 75% + 10%
Selectivity(P1)=75
(75+10)*100 =88%
N.B. Both parameters do not take into account W .
Both parameters do not take into account
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The 12 Principles of Green Chemistry
2) Atom economy (A.E.) =𝐌𝒐𝒍𝒆𝒄𝒖𝒍𝒂𝒓 𝑴𝒂𝒔𝒔 𝒐𝒇 𝒅𝒆𝒔𝒊𝒅𝒆𝒓𝒆𝒅 𝒑𝒐𝒅𝒖𝒄𝒕𝒔
𝐌𝒐𝒍𝒆𝒄𝒖𝒍𝒂𝒓 𝑴𝒂𝒔𝒔 𝒐𝒇 𝒂𝒍𝒍 𝒓𝒆𝒂𝒄𝒕𝒂𝒏𝒕𝒔*100
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The 12 Principles of Green Chemistry
Ambretone® (Toray)
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The 12 Principles of Green Chemistry
3) Wherever practicable, synthetic methods should be designed to use
and generate substances that possess little or no toxicity to human healthand the environment.
4) Chemical products should be designed to preserve efficacy of function
while reducing toxicity.
5) The use of auxiliary substances (e.g. solvents, separation agents, etc.)
should be made unnecessary wherever possible and innocuous when
used. (Process Mass Intensity)
6) Energy requirements should be recognized for their environmental and
economic impacts and should be minimized. Synthetic methods should be
conducted at ambient temperature and pressure.
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The 12 Principles of Green Chemistry
Life Cycle Assessment (LCA): from cradle to grave
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The 12 Principles of green chemistry7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
8) Unnecessary derivatization (use of blocking groups, protection/deprotection,
temporary modification of physical/chemical processes) should be minimized or
avoided if possible, because such steps require additional reagents and can
generate waste.
9) Catalytic reagents (as selective as possible) are superior to stoichiometric
reagents.
10) Chemical products should be designed so that at the end of their function
they break down into innocuous degradation products and do not persist in the
environment.
11) Analytical methodologies need to be further developed to allow for real-
time, in-process monitoring and control prior to the formation of hazardous
substances.
12) Substances and the form of a substance used in a chemical process should
be chosen to minimize the potential for chemical accidents, including releases,
explosions, and fires.
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1) It is better to prevent waste than to treat or clean up waste after it has been created
" In a ideal chemical factory there is, strictly speaking, no waste but only
products. The better a real factory make use of its waste, the closer it
gets to its ideal, the bigger is the profit“.
R. W. Hofmann, 1848
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5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Chemical Reactions: reagents, solvents, energy
Solvents
• they represent, in terms of mass, the majority of the materials introduced
into the chemical reaction system;
• they are not incorporated in the final product (auxiliary substances)and
must be recovered and treated as waste.
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5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Volatile Organic Solvents (VOCs)
VOCs are easy to remove (significant vapor presssure at room
temperature and relatively low boiling point (<250°C)).
Healthy Esffects of
VOCs
Dizziness
Fatihue
Conjunctival
irritation
Nausea
Headache
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Safety
ChemistryEngineering
process
5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Idieal Solvent
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5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Alternative Solvents 1 : benign non-volatile organic solvents (e.g. ethyl lactate)
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5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Sustainable Chemistry and Pharmacy 2016 21 22
Advantages Disadvantages
Non-toxic Distillation is energy intensive
Naturally occurring Poor solvent capacity properties for
organic molecules
Inexpensive Contaminated waste streams may be
difficult to treat
Non-flamable Incompatible with some compounds
High specific heat capacity-
exothermic reactions can be
more safely controlled
High specific heat capacity-difficult
to heat and cool rapidly
Opportunity for replacing VOCs
5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Alternative Solvents 2 : Water based processes
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Safety
ChemistryEngineering
process
5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Idieal Solvent = No Solvent
(Solvent-Free processes)
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5) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made
unnecessary wherever possible and, innocuous when used. (Process Mass Intensity)
Green. Chem. 2004, 43 25
6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Alternative Forms of energy 1: Microwave assisted organic synthesis (MAOS)
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Alternative Forms of energy 1: Microwave assisted organic synthesis (MAOS)
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Solvent-free Microwave assisted organic synthesis
Microwave assisted reactions in water
Radiation is absorbed by the reactants, giving enhanced
energy efficency
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Alternative Forms of energy 2 : Photochemical Reactions
Reagent 1*
Reagent 1
Light
Product
Reagent 2
D , Reagent 2
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Pure Appl. Chem. 2007, 1939
✓ Light is a clean and traceless reagent;
✓ mild reactions conditions.
✓ High energy demand of most articial light source.
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Sunlight✓ Naturally occurring (available in
large quantity);
✓ free energy source;
✓ fully renewable and zero
emissions;
✓ broad energy spectrum.
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Window ledge chemistry
Giacomo Ciamician, University of Bologna
✓ Discontinuous intensity;
✓ small amount of material can be
treated for day.
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Solar PhotoreactorsAscaridole synthesis
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
PROPHIS Parabolic tRough collector for Organic PHotochemical syntheses In Solar light
Flatbed reactor, Università James Cook (JCU) Australia, 2014
Parabolic Dish Solar Concentrator, Ege University, Turkey, 2004
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6) Energy requirements should be recognized for their environmental and economic
impacts and should be minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Window ledge chemistry
Solarbox
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7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Biomass: all living material may be considered as biomass but, commonly, only non-animal renewable resources tend to be referred to as biomass.
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7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Biomass: all living material may be considered as biomass but, commonly, only non-animal renewable resources tend to be referred to as biomass.
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7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Bioethanol: production of ethanol from fermentation of glucose-based cropssuch as sugar cane and corn starch using yeast.
Endo-β-1,4-glucanase
Cellubiohydrolase
β-glucosidase
Cellulose: n ≈ 3.000
Oligosaccharides: m< n
cellobiose glucose38
7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Bioethanol: production of ethanol from fermentation of glucose-based cropssuch as sugar cane and corn starch using yeast.
Disadvantages
✓ Waste disposal after the
manufacturing process
of ethanol;
✓ fermentation processes
typically give a product
with an ethanol
concentration of
between 7% and 15%.
Distillation is required to
obtain higher
concentration
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"L’uso degli oli vegetali come carburanti per i motori può sembrare
insignificante oggi, ma tali oli nel corso del tempo possono
diventare altrettanto importanti quanto il petrolio e il carbone; la
forza motrice potrà essere ottenuta col calore del Sole anche
quando le riserve dei combustibili liquidi e solidi saranno esaurite".
Rudolph Diesel, 1912
7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Biodiesel
Biodiesel from vegetable oils
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7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Syngas
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7) A raw material or feedstock should be renewable rather than depleting
whenever technically and economically practicable.
Chemicals from Fatty Acids
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Catalyst: a material whichchanges (usually
increases) the rate of
attainment of chemical
equilibrium without itself
being changed or
consumed in the process.
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Heterogeneous catalysis Homogeneous catalysis
Distinct solid phase Same phase as reaction medium
Readily separated Often difficult to separate
Readily regenerated and recycled Expensive/difficult to recycle
Long service life Short service life
Rates not usually as fast as homogeneous Often very high rates
Quite sensitive to poisons Usually robust to poisons
Low selectivity High selectivity
Often high energy process Often takes place under mild conditions
Poor mechanistic understanding Often mechanism well understood
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Haber Bosch process
N2 + 3H2 2NH3[Fe]
600°C150-200 bar
NH3
Ox
HNO3
NH4NO3
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Catalytic hydrogenation of Fatty Acids
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Biocatalysis: use of biological systems (or reagents) to catalyze the conversion of a substrate to the desired product.
✓ Opportunity for aqueous phase reactions;
✓ non-toxic, low hazard catalysts;
✓ energy efficient reactions under moderate
conditions of pH, temperature;
✓ high degree of selectivity.
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CN
nitrile idratasi
5°C, H2O
NH2
O
9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Production of acrylamide
Cleavage of galactose
Fructose synthesis
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
COOH
OH
MeOPycnoporus cinnabarinus
OH
MeO
O H
Vanilline synthesis
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Limitations of biocatalysis
✓ Stability of enzymes within a narrow range of pH and T;
✓ cost of enzymes and recovery difficulties once the
cycle has been completed;
✓ isolation of the products obtained;
✓ difficulty of using enzymes in solvents other than water.
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Photocatalysis: change in the rate of a chemical reaction or its initiation
under the action of ultraviolet, visble or infrared radiation in the presenceof a substance—the photocatalyst—that absorbs light and is involved in
the chemical transformations of the reaction partners.
IUPAC GOLD BOOK
Photocatalyst: catalyst able to produce, upon absorption of light,
chemical transformations of the reaction partners. The excited state ofthe photocatalyst repeatedly interacts with the reaction partners
forming reaction intermediates and regenerates itself after each cycle
of such interactions.
IUPAC GOLD BOOK
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9) Catalytic reagents (as selective as possible) are superior to
stoichiometric reagents.
Titanium dioxide-self cleaning window
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Designing Greener processes
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Designing Greener processes-Microreactors
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Ibuprofen synthesis
Ibuprofen Synthesis by BootsGreen Synthesis
✓ 6 steps;
✓ reagents rather than catalysts;
✓ copious amounts of waste.
✓ 3 steps;
✓ catalysts rather than reagents;
✓ less waste.
✓ last two steps 100% A.E. and
100% yields;
✓ CO
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Highly efficient synthesis of Sitagliptin
Presidential Green Chemistry Award 2006 and ICHEME AstraZeneca for sustainability award
✓ 3 steps;
✓ 50% increase in yield;
✓ less waste.
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Phenol Synthesis
Bakelite Polycarbonates
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Phenol Synthesis
Old Synthesis Green Synthesis
✓ 4 steps;
✓ copious amounts of waste;
✓ low atom economy.
✓ 3 steps;
✓ two steps 100% atom economy.
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